A high voltage igbt device with built-in ballast resistor

Abstract

The present invention provides a high-voltage IGBT device with built-in ballast resistance, the cell structure of which includes a first conductive type semiconductor P + collector region, metal collector, second conductivity type semiconductor buffer layer, second conductivity type semiconductor N ‑ Drift region, first conductivity type semiconductor P-type base region, heavily doped first conductivity type semiconductor P + Doping region, second conductive type semiconductor built-in ballast resistance region, and heavily doped second conductive type semiconductor N + In the emitter region, the second conductive type semiconductor built-in ballast resistance region replaces the part of the second conductive type semiconductor N+ emitter region that extends laterally below the gate structure, so that the second conductive type semiconductor built-in ballast resistance region is in the gate voltage control region The present invention utilizes the positive temperature characteristic of the ballast resistance value at high temperature to improve the short-circuit capability of the device; meanwhile, the thermal stability of the device in the forward blocking state is improved.

Description

Technical field [0001] The invention belongs to the technical field of power semiconductor devices, and specifically relates to a high-voltage IGBT (Insulated Gate Bipolar Transistor) device with a built-in ballast resistor. Background technique [0002] Insulated Gate Bipolar Transistor (IGBT) has the advantages of high MOSFET input impedance, simple driving circuit, and fast switching speed, as well as the advantages of high current density and reduced saturation voltage of bipolar transistors. One of the mainstream power switching devices in the electronics field; widely used in high-voltage and high-current fields, such as wind power generation, rail transit, and smart grids. In practical applications, the IGBT will encounter load short-circuit conditions. At this time, the IGBT is subjected to the test of high voltage and high current at the same time. The temperature of the chip rises sharply in a short period of time and heat builds up, which eventually causes the device t...

AI Technical Summary

Problems solved by technology

For IGBT devices with traditional EBR structure, the emitter ballast resistance consists of a strip N + emitter constitutes because N + The doping concentration in the emitter region is high, and the mobility is mainly dominated by the scattering of ionized impurities. The resistance usually exhibits a negative temperature coefficient, that is, the emitter ballast resistance decreases as the temperature increases; under low temperature and low current conditions, EBR A large resistance value will increase the conduction loss of the IGBT power device. Under the condition of high temperature and high current after a short circuit, the resistance value of the EBR becomes smaller, which cannot effectively limit the short circuit saturation current, and the short circuit capacity will continue to increase as the temperature rises. Weakened; therefore, an IGBT device with an EBR structure with a positive temperature coefficient can effectively improve the short-circuit capability of the device

The prior art scheme shows that ballast resistors with positive temperature coefficients can be used at N + It is realized by introducing nickel-iron alloy or deep-level acceptor impurities into the emission area, but the technical scheme is difficult to realize, and it is not compatible with the traditional manufacturing process, and its resistance manufacturing process itself has high-temperature reliability problems

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